The present invention relates to a new and improved steering apparatus and, more specifically, to a new and improved power steering apparatus having an electric motor to turn steerable vehicle wheels.
A power steering apparatus having an electric motor to turn steerable vehicle wheels is disclosed in U.S. Pat. No. 4,415,054. The steering apparatus disclosed in this patent has a torque sensor which is actuated upon rotation of the steering wheel. Actuation of the torque sensor causes an electronic control unit to energize the electric motor. The electric motor drives a ball nut. The ball nut cooperates with a screw attached to a rack of a rack and pinion steering mechanism. Rotation of the ball nut moves the screw and the rack axially to effect turning of the vehicle wheels.
In the power steering apparatus of U.S. Pat. No. 4,415,054, the rack extends through a housing fixed with respect to the vehicle and is attached through steering linkages directly to the steerable wheels of the vehicle.